Automatic train-control apparatus



June 26,. 1928.

1,675,252 P. J. CLIFFORD AUTOMATIC TRAIN CONTROL APPARATUS Original Filed Jan. 5, 1923 SSheets-She'et 1 v z z I VAR. PR c 5 7 1 3 P 6] 1 (A. [d 5 Q? JKKK Inuenior:

Patrick C Z g'fforfl 1 June 26, 1928. 1,675,252

P. J. CLIFFORD AUTOMATIC TRAIN CONTROL APPARATUS I Original Filed Jan. s, 1923 s Sheets-Sheet 2 v Inyenfor:

Patrick JCZWoL'd,

June 26, 1928. 1,675,252

P. J. CLIFFORD AUTOMATIC TRAIN com'nor, APPARATUS Original Filed Jan. 5, 1923 3 Sheets-Sheet 3 Inuenior:

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A a 71w Anya.

Patented June 26, 1928..

UNITED STATES PATRICK J. CLIFFORD, OF FALLS, PENNSYLVANIA, ASSIGNOR, BY MESNE ASSIGN- MENTS, T TRAIN CONTROL CORPORATION OF AIVIERICA, A CORPORATION OF DELA- WARE.

AUTOMATIC TRAIN-CONTROL APPARATUS.

Application filed January 5, 1923, Serial No. {310,880. Renewed August 9, 1927.

This specification concerns train control apparatus of the general character disclosed in my application for Letters Patent of the United States filed April 17, 1922, No. 553,429. My present improvement includes as one feature means for taking care of conditions when the vehicle is turned in respect to its position for normal traffic, and is running rear end first, so that the signal or signals on the engine will not give a false indication. In addition to forms of primary relay on the engine, shown in said application, I have included herein other forms which may be used as will be set forth herematter, in all of which, however, the relay is located in a connection in continuous electrical contact with the track rail system of the block so as to be operated by current resulting from the drop in potential between the points where contact is made with said track rail system.

In the accompanying drawings:

Figure 1 is a diagram of one. form of primary relay connection.

Fig. 2 is a diagram of another form of relay connection.

Fig. 3 is still another form.

Fig. 4 is a diagram of a form of relay which will compensate for shocks and jars.

Figs. 5 and 6 are diagrammatic views of other forms of relays and their connections.

Figs. 7 and 8 are diagrams of circuit changing means for securing like circuit conditions to the apparatus on the vehicle,

) whether the vehicle is advancing head or rear end first.

Fig. 9 is another form of means for securing the effect of Figs. 7 and 8 from the governor on the engine.

Figs. 9 and 9 show modified forms of primary relays.

Fig. 10 shows the relay more in detail.

In these drawings 1, 2 are ordinary rails of the trackway, divided into blocks insulated from each other according to standard practice in signalling systems. The vehicle, which may be considered to be the engine, or engine and tender combined, or any suitable carrier for the apparatus, is or are of standard form.

The relay PR is in an electric connection, such as 3, the terminals of which are in contact with points on the track rails, and in the forms shown the contact is made through the wheels and axles of the vehicle, the said relay being adapted to be operated by the current flowing through this connection due to the drop in potential between the said points, where the wire is in electrical connection through contacts (the ordinary wheels in the example illustrated) on the .energized rail. As an example of means for energizing the trackway rail, I show in Fig. 1 a battery NP and connections leadirig therefrom to the ends of the rail of the block, the insulated joints between which and the adjacent block are shown at 4. This relay is polarized, having two contacts p, p electrically connected as at 5, the leads being shown at 6, 7 and the swinging armature at 8 to which the lead 6 is connected. Connection 5 will be omitted as noted hereinafter.

One way of electrically connecting the wire 3 with the track rail system to receive current therefrom is to join the ends of the wire to the upper bearing members or brasses in the journal boxes of the ordinary axles of the vehicle, so that these bearings, the wheel journals and the wheels will be in this circuit, though I do not limit myself inthis particular, it being obvious, however, that it is of material advantage to pro- Vide such a connection as will not require alteration of standard equipment, but will only entail connection therewith or mounting thereon. As just stated above, the vehicle is of standard form with ordinary axles, and therefore, as set forth in my application of even date herewith, Serial Number 610,879, no insulation of wheels, axles or other parts of the standard equipment is employed, and by reason of taking the current through the ordinary bearing members or brasses of the journal boxes I avoid the use of collector rings and brushes which by their frictional contact will generate current which will unduly aflect the primary relay. The relay PR is responsive to the presence or absence of a prescribed current in the track rail system and it is responsive also to the changes in polarity of the current received from the track rail system. This prescribed current may be that of the wayside signal system or it may be a current iniposed on the track rail system where no wayside signal system is employed or it may be that which is imposed on the trackage in addition to that used for operating the signal system. In other words, the relay may be calculated to pick up the prescribed current and to remain unaffected by the signal current or by current generated dynamically from therunning gear. The change in polarity of the current through the relay Will result from changes in polarity of the circuit in the track rail system, such as may be made to secure an advance signal indication in the engineers cab, or for responding to change in the polarity of the track rail system circuit under other circumstances.

This primary relay may be used to control signals in the cab correspondlng to ordinary wayside block signals, and in addition it may cooperate to control advance caution signal indications, and these cab signals may be used either with or Without the wayside signals. The primary relay is also used to control train stop apparatus on the train and this function may be performed alone or in conjunction with the cab signals. The primary relay preferably exerts its control upon apparatus carried by the vehicle through a slow acting relay SAR to take care of any momentary deenergizing of the primary relay due to crossing the insulated rail joints or due, for instance, to sand on the track rail system temporarily interrupting the circuit, or to take care of the reversing of the primary relay due to a change in the polarity of the current. The control exerted by the primary relay is continuous, it being in electrical connection with the track rail system of the block con stantly, the track rail system being of standard type with the rails electrically con tinuous from end to end of the block.

In Fig. 1 the primary relay PR is in a connection 3 on one side of the vehicle and with points spaced apart along one rail. In Fig. 2 the relay is in a connection in parallel, on opposite sides of the vehicle and with both rails. In Fig. 3 the connection in which the relay is located and in which the current results from the drop in potential, extends diagonally of the vehicle from, say, the right hand front wheel to the left hand rear Wheel, as in said application.

In Fig. 4: I show a duplex form of relay having a pair of normal polarity contacts and a pair of reverse polarity contacts connected in multiple. The normal contact of one relay is at the right of the svvinglng contact arm, whereas the normal contact of the other relay is at the left of its contact arm.

The reverse polarity contacts are likewise located at dilleieut sides oi their respective arms. Under a prescribed energized condi' m oi the track rail system, both arniaturcs be on their normal polarity contacts, as sh. wn, and under an absence of this condition they will .ig to neutral position, whereas upon change of polarity of the track current both armatures will be on their reverse polarity contacts. in either closed position at the arms the relay will be substantially unatlected by shocks and jars because the same shock which tends to dislodge one armature will press the other harder upon its contact and hence the circuit controlled by the relay will be maintained, or it one circuit connection in which the relay is immediately located is broken, the other will serve alone to maintain the circuit.

In Fig. 5 is shown a primary relay having its coil connected in multiple with alternate axles so that there will be no interruption oi current in passing an insulated rail joint.

In (S is shown a primary relay connection having two armaturcs and two sets of contact. The coil for one of these relay n'iembers is in a branch circuit of the track rail system extending diagonally of the engine and completed through the wheels, and the coil of the other section is in a similar conductor but extending diagonally of the tender. The purpose here is to prevent interruption ot the current through the relay when passing the insulated rail joints between the blocks.

In each of the above figures the coil of the relay shown at 0. The relay may be of the Depre DArsonval type for direct current, with polarized action of its armature or armatures, and closing on its contacts on potential say. for instance, above plus or minus 1.5 millivolts. The current. imposed on the track rail system may he, say, 7 amperes, though it will be understood that these figures may be varied. As in my previous application, the energized primary relay, when energized by the prescribed current, will hold the train stop apparatus in condition with the brakes oft and upon the 'absence of said prescribed current the pri lnary relay will assume neutral position, resulting in the brakes being applied.

In so far as the apparatus on the vehicle is concerned. this may be like that disclosed in said application, both as regards train stopping means and also s gnalling means, and this is true also of the various circuits. In other words, the subject matter of said application is to be regarded as illustrating how the relay herein may be utilized and this may be regarded as a part of this specification.

It w'll he understood that where features of the relay above described in connect-ion with the several views are susceptible of being embodied in one organization, that the disclosure is supposed to cover this. For instance, the diagonal connection can be used in Fig. 4, or both connections can be made on one side of the engine, or the duplex instrument of Fig. 4 can be wired as in Figs. 5 or 6.

Where the charge in polarity of the prescribed current is to be utilized, for instance, in getting an advance signal indication the electrical connection at 5 between the points p ,0 will be omitted.

It does not appear necessary to illustrate herein all the mechanism which is controlled by the primary relay, it being thought sufficient to indicate the slow acting relay as representative of any mechanism which may be used and which when energized will hold the brakes off, and will cause the setting of the brakes in the absence of said prescribed current in the primary relay.

I have provided means to maintain the circuit on the engine. in its normal path when the position of the engine is reversed, i. e., running backward, so that the signal or signals will not give a false indication on said engine, when thus turned in respect to its position for normal traflic.

As an example of means for doing this I show in Figs. 7 and 8 a revolvable drum 9 which is connected to the reversing lever of the engine so as to be turned through, say, 90, when the lever is moved in either direction.

It has contacts for changing the electrical connections leading from the primary relay so that when that relay has its connection to the rails reversed with respect to the normal polarity of the rails through the turning around of the engine, these contacts will again reverse the connections, so that the indication received by the locomotive apparatus will be normal in respect to the track polarity. In other words, it accomplishes a second reversal which results in a normal condition. Or to put the matter in another way, despite the reversal in the position of the armature of the relay due to the change in direction of current passing through its coil when the engine advances rear end first. the path of current through the apparatus on the vehicle w ll be maintained as long as the polarity of the track circuit remains unchanged. it being understood that the reversing mechanism on the engine has set the rotary switch 9 to accomplish the result stated.

I have shown only one signal lamp. at AYS, as this w ll serve as an illustration of the principle involved. Suppose the armature of the polarized relay PR is on contact 16, Figure 7, current would take the path of the solid arrows and signal lamp AYS would be under one condition, in the instance shown, not lighted.

Now if the polarity of the current through primary relay PR were reversed due to a change in the polarity of the track circuit while the engine maintained its same direction of travel, that is with the rotary drum in the position of Fig. 7. the reversing of the armature of relay PR to contact 18 would cause a change in the path of the current as indicated by the dotted arrows Fig. 7 and signal AYS would be changed, that is in this instance it would be lighted as it should, because of the change in polarity of the trackagc current.

The change in polarity of the track circuit will be brought on by the occupation of the second block ahead and the resultant displaying of signal AYS will give an ad Vance caution indication i. e. an advance yellow signal light to forewarn the engineer that the second block ahead obstructed. I have not illustrated herein the means for accomplishing this change in polarity of the track circuit to get the advance indication above referred to as this is disclosed in application of even date Serial No. 610,879.

Now to take care of the change in the polarity of the current supplied to PR due to the engine being turned around and advancing tender first.

The rotary contact drmn will shift to the position of Fig. 8 when the reversing lever of the engine is operated to make the engine advance with tender ahead, so that de spite the reversal of the armature of relay PR onto contact 18 the direction of the current will be the same as shown by the solid arrows as when the armature was on contact 16 of Fig. 7 and hence the signal AYS will not be changed as a consequence ot the vehicle advancing tender first instead of engine first. But should the polarity of the track circuit change while the vehicle is advancing in reversed position the signal will indicate this change because then the circuit thereto will be completed through contact 16 and the rotary switch in the dotted arrow direction Fig. 8.

In either case circuit through the slow acting relay SAR will be maintained, switch 28 clos ng when the current is in the dotted arrow course, due to energizing of coil AY. This SAR relay is representative of apparatus on the vehicle for securing an application of the brakes when prescribed current is absent from the track due to caution or danger conditions and for holding the l 'akes off when energized as set forth in the applications above referred to.

The apparatus on the vehicle is controlled by the SAR' relay.

Forms of switches other than the rotary one above noted may be employed in connection with the engine reversing mechanism. Thus a sliding switch arrangement may be used connected with the reversing lever of the engine or a knife switch may be employed, or the switch may be combined with the governor instead of *ith the reversing lever.

Figure 9 shows such a switch in which a sleeve 10 is operated by a coarse thread on the governor shaft 11. The sleeve carries contacts 12. 13, cooperating with fixed contacts 14, 15 to control the course of the current from the PR relay to the signal and train stop mechanism as above indicated. The sleeve is pressed or pulled by spring 19. WVhen the governor shaft is turned the sleeve will be moved by the screw to make contact at either one end or the other and having made contact at about the time the sleeve moves out of connection with the coarse screw it will remain in this position pressed or pulled, however, by its spring until the direction of motion of the governor shaft changes when the spring will force it into engagement with the coarse screw which will cause the sleeve to reverse its position and maintain the circuit to the apparatus on the Vehicle in the same direction as before. The invention is not limited to the location of the shitting contacts in the connections between the polarized relay and the apparatus on the vehicle as a suitable circuit changer may be located in the branch circuit in which the polarized relay is located, that is, at a point between the primary relay and the track rail system.

It will be understood that the primary relay shown herein may be used with the apparatus and system disclosed in said application of even date.

'Referring to Fig. 10, the galvanometer form of relay may be generally like that made by The \Veston Electrical Instrument Co. of Newark, N. J., Model 30, and disclosed as to its general features in Letters Patent of the United States of Edward Vt'eston, for instance, 611,722, Oct. 4, 1898, or 446,498, Feb. 17, 1891. The pointer or swinging contact arm is carried by a spool arranged between poles of a permanent magnet and capable of having rotative movement when it receives current from the track rail system, and thus the said arm is set against either one contact or the other. Vhen no current is passing through the spool from the trackage, the pointer assumes neutral position and as the traflic rail and frame of the vehicle provides a bridge between the terminals of the spool, tendency of the spool and pointer to vibrate under or shock will produce current through this bridge and the spool which will oppose vibration of the spool, and thus the pointer or swinging arm will be steadily maintained in neutral position, thus rendering the device suitable for mounting on a locomotive.

\Vhere in the claims the term train control means is used, it is in its generic sense to include signal means on the vehicle, brake means, or both.

I11 Fig. 9 is shown a primary relay having its conductor in two sections displaced relatively to each other along the rails so that the current may be picked up uninterruptcdly despite the fact that the relay passes over insulated joints.

Fig. 9" is a view of a different form of primary relay made up of instruments in duplicate with their conductors displaced relative to each other along the rail so that when the conductor of one instrun'ient is crossing an insulated joint the conductor of the other instrument will be in service, both instruments controlling the same circuit con- 11 ctions on the vehicle.

Certain features relating to the primary relay are claimed in a divisional application tiled May 17, 1928. and in an application tiled Feb. 20, 1923, No. 620,286.

I claim:

1. In train control apparatus, the combination ot means for imposing direct electric current upon the track rails, apparatus on the vehicle. and a primary relay on the ve hicle tor controlling said apparatus without amplification of said imposed current, said relay being polarized and being in a connection in continuous electric contact with the tack rails through parts of the standard uninsulated vehicle to receive direct current from said track rail system due to the potential drop between the points of contact with the track rails, and circuits controlled by said polarized relay according to whether its armature is closed on it; normal polarity contact or on its reverse polarity contact, substantiall as described.

2. In train control apparatus the combination of a primary polarized relay on the vehicle in a branch circuit from the track rails to receive current therefrom due to the drop in potential between the points of contact of said circuit with the track rails. :Jignal means on the vehicle and means on the vehicle for maintaining the same circuit conditions in respect to the signal means whether the vehicle is advancing front end or rear end first. comprising shifting contacts and means for shifting them when the engine is reversed, said circuit maintaining means being interposed between the primary relay and the signal means substantially as described.

3. In combination in train control apparatus, a primary polarized relay on the vehicle, in a branch circuit from the track rails to receive current therefrom due to the potential drop between the point; of contact of said circuit therewith, the armature of said relay controlling two paths of current, one of which includes a signal and both of which include a relay controlling apparatus on the vehicle for controlling the brakes, and means interposed between the primary relay and said signal and relay operated by the reverse action of mechanism on the engine, when reversed, for maintaining the normal paths of the current whether the vehicle advances head end first or rear end first and for changing the current path relative to the signal when the polarity of the track rails circuit changes and the polarized relay is operated, substantially as described.

4. In train control apparatus the combination of a primary polarized relay on the vehicle in a branch circuit from the track rails to receive current therefrom due to the drop in potential between the points of contact of said circuit with the track rails, signal means on the vehicle and means on the vehicle for maintaining the same circuit conditions in respect to the signal means whether the vehicle is advancing front end or rear end first, comprising shifting contacts and means for shifting them when the engine is reversed, said shifting contacts being interposed between the primary relay and the said signal and maintaining means, said shifting means being operated by the engine governor, substantially as described 5. In train control apparatus the combination of a primary polarized relay on the vehicle in a branch circuit from the track rails to receive current therefrom due to the drop in potential between the points of contact of said circuit with the track rails, means on the vehicle controlled by said relay, and means on the vehicle for maintaining the same circuit conditions to said first mentioned means whether the vehicle is advancing front end or rear end first, comprising shifting contacts and means for shifting them as a consequence of the engine being reversed said shifting contacts being interposed between the primary relay and the said signal and maintaining means.

6. In combination in train control apparatus, means for imposing current on the track rails, relay means on the vehicle in a circuit connection extending diagonally thereof, in which circuit the wheels are included, and apparatus 0n the vehicle controlled by said relay means, the passage of current through said connection being due to the potential drop betwen the points on the traflic rails where said wheels contact therewith, the vehicle being of standard uninsulated type, substantially as described.

7 In combination in train control apparatus, means for imposing a prescribed current upon the track rails, relay means on the vehicle deriving its current from two branch circuit connections from said track rails, due

to the drop in potential between the points on the track rails where the said connections contact therewith, and means on the vehicle controlled by the relay means.

8. In combination in train control appa ratus, means for imposing electric current on the track rails, duplex relay means on the vehicle in a branch circuit connection from said track rails receiving current due to the potential drop between the points where said connection -contacts with the track rails, said relay having two armatures closing against their respective contacts in opposite direction and each armature controlling the same circuit or circuits, said armatures and contacts being so disposed that shock or jar tending to open one will set the other harder upon its contact, substantially as described.

9. In combination in train control apparatus, means for imposing electric current on the track rails, duplex relay means on the vehicle in a branch circuit connection from said track rails receiving current due to the potential drop between the points where said connection contacts with the track rails, said relay having two armatures closing against their respective contacts in opposite direction and each armature controlling the same circuit or circuits, said armatures and contacts being so disposed that shock or jar tending to open one will set the other harder upon its contact, said relay being polarized and having a normal polarity and a reverse polarity contact for each armature, substantially as described.

10. In combination in train control apparatus, controlling means on the vehicle, primary relay means for controlling the same, mounted on the vehicle and comprising two armatures, having their contacts displaced relatively in respect to their armatures, and circuit connections for said relay to the track rails, to receive current therefrom.

11. In combination in train control apparatus, controlling means on the vehicle, primary relay means for controlling the same, mounted on the vehicle and comprising two units with their coils and armatures, having their contacts displaced relative to each other in respect to their armatures, and a separate circuit connection for each relay unit, one with one rail and the other with the other rail, both of said units controlling the same circuit connections in which said controlling means is included.

12. In combination in train control apparatus, primary rela means on the vehicle and circuit connections for controlling the same from the electrical condition of the track rails, said circuit connections being in multiple and displaced along the track rails relative to each other to keep the relay under control in passing joints of the traliic rails.

13. In combination in train control apparatus, a primary relay means on the vehicle and a plurality oi circuit connections thereto from the track rails, said connections being displaced relative to each other along the track rails to maintain the relay energized in passing joints ot the rail, substantially as described.

14. In combination in train control apparatus. a primary relay on the vehicle for controlling ircuit connections in which control appliances on said vehicle are located, said relay including a rotative coil with a contact arm connected to rotate therewith, a conductor in which said relay is located, having its terminals connected with the brasses of the journal boxes to receive current from the trailic rails due to the drop in potential lit-tween the points of contact with sai: rails and without amplification, said vehicle being of vtandard uninsulated type, and said traltic rails totalling a bridge between the terminals of said coil to hold the contact arm steady in neutral position, substantially as described.

15. A train control system comprising means for imposing electric potential upon the track system of an occapicd blocl. and absenting said electric potential from a cantion block, said means having one lead connected to the trzdlic rail :ystcm ol' the block at one end and the other lead connected to thc iratli. rail other Uitl and means controllimg said current. a primary relay on the vehicle in a conductor having it terminals in continuous physical and electrical contact with the trark system. and receiving current therefrom due to the potential drop between the points of contact of its terminals with said ti'acl; sys tem. and without annpliticatiou, said relay having a contact arm, a I'Utrlttlill? armature in a lililfllltlitfi ticld and connected in said conducti and, carrying said arm, th terminals ot said coiuluctor being bridged by thc \chiclc t :nnc and/or track system to dampen the vibration ot said armature and contact arm and render the same in eusible to shocl: when the lattcr is in neutral position. and lJIiilit applying men which is energized through sa d i-clay to hold the brakes ott and when dcenergizcd. by said contact arm a sumii'ig neutral position, causing a bruise application, substantially as described.

lti. A train control system compri in means tor imposing electric potential the track srstcm ot an occupied block and .-:bsenting said electric potential from a cau tion block. a primary relay on the vehicle in a conductor having its terminals in continuous physical and electrical contact with the track system through the journal bearings of the vehicle, and r ceiving current thercirom due to the potential drop bet ween the points o't contact of its terminals with aid track system, and without amplification,

upon system ot' illt blocl; at the said relay having a contact arm, a rotatable armature in a magnetic field and connected in said conductor and carrying said arm, the terminals of said conductor being bridged by the vehicle frame and/or track system to dampen the vibration of said armature and contact arm and render the same insensible to shock when the latter is in neutral position, and brake applying means which is energized through said relay to hold the brakes ofl' and when deenergized, by said contact arm assuming neutral position, causing a brake application, substantially as described.

17 A train control system comprising means for imposing electric potential upon the track system of an occupied block and absenting said electric potential from a cantion block, a primary relay on the vehicle in a conductor having its terminals in continuous physical and electrical contact with the track system, and receiving current therefrom due to the potential drop between the points of contact of its terminals with said track system, and without amplification, said relay having a contact arm, a rotatable armat are in a magnetic field and connected in said conductor and carrying said arm, the terminals of said conductor being bridged by the vehicle frame and/or track system to dampen the vibration of said armature and contact arm and render the ame insensible to shock when the latter in neutral position, and a slow acting relay in a circuit controlled by the primary relay, and train control means controlled by the slow acting relay, substantially as described.

18. A train control system comprising means for imposing electric potential upon the track system of an occupied block and absenting said electric potential from a cantion block, a primary relay on the vehicle in a conductor having its terminals in continuous physical and electrical contact with the track system, and receiving current therefrom due to the potential drop between the points of contact of its terminals with said track system, and without amplification, said relay having a contact arm, a rotatable armature in a magnetic field and connected in said conductor and carrying said arm, the terminals of said conductor being bridged by the vehicle frame and/or track system to dampen the vibration of said armature and contact arm and render the same insensible to shock when the latter is in neutral position, said primary relay being polarized to make different contacts for difi'erent directions of the current, a slow acting relay controlled by said primar relay, and brake mechanism on the vehicl e controlled by said relays.

19. In train control apparatus, and in combination, a polarized primary relay 0n the vehicle in a conductor, receiving current from the track rail system due to drop on potential between the points of contact of said conductor With said rail system, train control means on the vehicle in circuit with the contact of the primary relay, said primary relay changing the polarity of the current in said circuit, according to changes of polarity of the track circuit, and means on the vehicle interposed between said relay and said train control means for maintaining automatically the same condition of said circuit in respect to said train control means Whether the vehicle is advancing front end or rear end first, substantially as described.

In testimony whereof I aflix my signature.

PATRICK J. CLIFFORD. 

